Terminal, control device, communication method, communication system, communication module, program, and information processing device

ABSTRACT

A terminal communicating with a network including a forwarding device for forwarding a packet and a control device for controlling the forwarding device in accordance with a request from the forwarding device, includes a communication unit that receives a processing rule indicating that a packet for communicating with a first destination is changed so as to communicate with a second destination, from the control device, a storage unit that stores the received processing rule, and a processing unit that in a case of communicating with the network, changes a destination of a packet in accordance with a processing rule that corresponds to the packet by referring to the processing rule stored in the storage unit.

REFERENCE TO RELATED APPLICATION

The present application is a Continuation application of U.S. patentapplication Ser. No. 14/112,520, filed on Oct. 17, 2013, which is basedon International Application No. PCT/JP2012/002677, filed on Apr. 18,2012, which is based on Japanese Patent Application No. 2011-092320,filed on Apr. 18, 2011, the entire contents of which are incorporatedherein by reference.

TECHNICAL FIELD

The present invention relates to a terminal, a control device, acommunication method, a communication system, a communication module, aprogram, and an information processing device, and relates tocommunication technology in a network in which the control deviceperforms centralized control of forwarding devices.

BACKGROUND

In recent years, technology known as OpenFlow has been proposed (referto Patent Literature 1, and Non-Patent Literatures 1 and 2). InOpenFlow, communication is treated as end-to-end flow, and path control,recovery from failure, load balancing, and optimization are performedper flow units. An OpenFlow switch as specified in Non-Patent Literature2 is provided with a secure channel for communication with an OpenFlowcontroller, and operates according to a flow table in which appropriateaddition or rewriting is instructed by the OpenFlow controller. In theflow table are definitions of sets of matching rules (Header fields) forcollation with packet headers, flow statistical information (Counters),and actions (Actions) defining processing content, for each flow (referto FIG. 24).

For example, when an OpenFlow switch receives a packet, an entry issearched for that has a matching rule (refer to header field in FIG. 24)that matches header information of the received packet, from the flowtable. As a result of the search, in a case where an entry matching thereceived packet is found, the OpenFlow switch updates the flowstatistical information (Counters) and also implements processingcontent (packet transmission from a specified port, flooding, dropping,and the like) described in an Actions field of the entry in question,for the received packet. On the other hand, as a result of the search,in a case where an entry matching the received packet is not found, theOpenFlow switch transmits a request for entry setting with respect tothe OpenFlow controller via a secure channel, that is, a request todetermine a path of the packet based on source and destination of thereceived packet. The OpenFlow switch receives a flow entry correspondingto the request and updates the flow table. In this way, the OpenFlowswitch uses the entry stored in the flow table as a processing rule toperform packet forwarding.

CITATION LIST Patent Literature (PTL) [PTL 1]

-   WO Pamphlet No. WO2008/095010A1

[PTL 2]

-   Japanese Patent Kokai Publication No. JP-P2004-064182A

Non-Patent Literature (NPL) [NPL 1]

-   Nick McKeown, and 7 others, “OpenFlow: Enabling Innovation in Campus    Networks”, [online] [search conducted Apr. 4, 2011] Internet URL:    http://www.openflowswitch.org//documents/openflow-wp-latest.pdf

[NPL 2]

-   “OpenFlow: Switch Specification” Version 1.0.0. (Wire Protocol    0x01), [search conducted Apr. 4, 2011] Internet URL:    http://www.openflowswitch.org/documents/openflow-spec-v1.0.0.pdf

SUMMARY

The following analysis is given by the present invention. In thetechnology disclosed in Patent Literature 1 and Non-Patent Literatures 1and 2, a controller determines an entry for packet processing inaccordance with a request transmitted from a switch, and sets thedetermined entry with respect to the switch. In such a centralizedcontrol type of communication system, there is a problem of load on thecontroller. A reason for this is that, since the controller centrallycontrols a plurality of switches and calculates entries with respect torequests transmitted from the plurality of switches, the processing loadon the controller increases.

Furthermore, the controller may set an entry prescribing processing forrewriting header content of a packet with respect to a switch. In thistype of case, there is a problem in that the load required for packetprocessing in a switch increases.

Patent Literature 2 discloses a gateway control device for controlling agateway. However, Patent Literature 2 does not disclose a measure forreducing load on a gateway or a gateway control device.

According to a first aspect, there is provided a terminal thatcommunicates with a network including at least one forwarding device forforwarding a packet, and a control device for controlling the forwardingdevice(s) in accordance with a request from the forwarding device. Theterminal includes: a communication unit that receives a processing ruleindicating that a packet for communicating with a first destination ischanged so as to communicate with a second destination, from the controldevice; a storage unit that stores the received processing rule; and aprocessing unit that in a case of communicating with the network,changes a destination of a packet in accordance with a processing rulethat corresponds to the packet by referring to the processing rulestored in the storage unit.

According to a second aspect, there is provided a control device thatsets a processing rule for a packet with respect to a forwarding devicefor forwarding packets. The control device includes: a request receivingunit that receives an access request transmitted from a terminal foraccessing a network in which the forwarding device processes the packetin accordance with the processing rule; a control unit that generates aprocessing rule indicating that a packet for communicating with a firstdestination is changed so as to communicate with a second destination;and a communication unit that transmits the generated processing rule tothe terminal.

According to a third aspect, there is provided a communication methodfor controlling at least one terminal communicating with at least onenetwork including a forwarding device for forwarding a packet, and acontrol device for controlling the forwarding device(s) in accordancewith a request from the forwarding device. The method includes: areceiving step of receiving a processing rule indicating that a packetfor communicating with a first destination is changed so as tocommunicate with a second destination, from the control device; a stepof storing the received processing rule; and a processing step of in acase of communicating with the network, changing a destination of apacket in accordance with a processing rule that corresponds to thepacket by referring to the processing rule stored in the storage unit.It is to be noted that the present method is linked with a specificapparatus, which is a terminal(s) for communicating with a networkincluding at least one forwarding node and a control device.

According to a fourth aspect, there is provided a communication systemincluding at least one forwarding device for forwarding a packet, acontrol device for controlling the forwarding device(s) in accordancewith a request from the forwarding device, and at least one terminalcommunicating with a network including the forwarding device(s) and thecontrol device. The control device comprises a control unit thatdetermines a processing rule indicating that a packet for communicatingwith a first destination is changed so as to communicate with a seconddestination. The terminal comprises: a communication unit that receivesthe processing rule determined by the control device, from the controldevice; a storage unit that stores the received processing rule; and aprocessing unit that in a case of communicating with the network,changes a destination of a packet in accordance with a processing rulethat corresponds to the packet by referring to the processing rulestored in the storage unit.

According to a fifth aspect, there is provided a communication moduleinstalled in a terminal communicating with a network including at leastone forwarding device for forwarding a packet, and a control device forcontrolling the forwarding device(s) in accordance with a request fromthe forwarding device. The module includes: a communication unit thatreceives a processing rule indicating that a packet for communicatingwith a first destination is changed so as to communicate with a seconddestination, from the control device; a storage unit that stores thereceived processing rule; and a processing unit that in a case where theterminal communicates with the network, changes a destination of apacket in accordance with a processing rule that corresponds to thepacket by referring to the processing rule stored in the storage unit.

According to a sixth aspect, there is provided a program that executes,in a terminal communicating with a network including at least oneforwarding device for forwarding a packet, and a control device forcontrolling the forwarding device(s) in accordance with a request fromthe forwarding device; a process of receiving a processing ruleindicating that a packet for communicating with a first destination ischanged so as to communicate with a second destination, from the controldevice; a process of storing the received processing rule; and a processof in a case where the terminal communicates with the network, changinga destination of a packet in accordance with a processing rule thatcorresponds to the packet by referring to the processing rule stored inthe storage unit. It is to be noted that the program can be recorded ina computer readable recording medium which is non-transient. That is,the present invention can be embodied as a computer program product.

According to a seventh aspect, there is provided an informationprocessing device that transmits to a terminal a program for executing,in the terminal that communicates with a network including at least oneforwarding device for forwarding a packet, and a control device forcontrolling the forwarding device(s) in accordance with a request fromthe forwarding device: a process of receiving a processing ruleindicating that a packet for communicating with a first destination ischanged so as to communicate with a second destination, from the controldevice; a process of storing the received processing rule; and a processof in a case where the terminal communicates with the network, changinga destination of a packet in accordance with a processing rule thatcorresponds to the packet by referring to the processing rule stored inthe storage unit.

The meritorious effects of the present invention are summarized asfollows

According to the present disclosure, in the technology for performingcommunication by the control device centrally controlling forwardingdevices, it is possible to reduce load on the control device and theforwarding devices.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a diagram showing an example of a configuration of the presentdisclosure.

FIG. 2 is a diagram showing an example of a configuration of the presentdisclosure.

FIG. 3 is a diagram showing an example of a table storing processingrules.

FIG. 4 is a flowchart showing an example of operations of the presentdisclosure.

FIG. 5 is a flowchart showing an example of operations of the presentdisclosure.

FIG. 6 is a diagram showing an example of a configuration of a firstexemplary embodiment of the present disclosure.

FIG. 7 is a diagram showing an example in which the configuration ofFIG. 6 is applied to an access control system.

FIG. 8 is a diagram showing an example of authentication information.

FIG. 9 is a diagram showing an example of communication policyinformation.

FIG. 10 is a diagram showing an example of resource information.

FIG. 11 is a diagram showing an example of a communication policy.

FIG. 12 is a diagram showing an example of a configuration of a controldevice.

FIG. 13 is a sequence diagram showing an example of operations of thefirst exemplary embodiment.

FIG. 14 is a sequence diagram showing an example of operations of thefirst exemplary embodiment.

FIG. 15 is a sequence diagram showing an example of operations of thefirst exemplary embodiment.

FIG. 16 is a sequence diagram showing an example of operations of asecond exemplary embodiment.

FIG. 17 is a diagram showing an example of a communication policy.

FIG. 18 is a diagram showing an example of a configuration of a thirdexemplary embodiment.

FIG. 19 is a diagram showing an example of a configuration of a fourthexemplary embodiment.

FIG. 20 is a diagram showing an example of a configuration of a fifthexemplary embodiment.

FIG. 21 is a diagram showing an example of a configuration of a sixthexemplary embodiment.

FIG. 22 is a diagram showing an example of a configuration of a seventhexemplary embodiment.

FIG. 23 is a sequence diagram showing an example of operations of theseventh exemplary embodiment.

FIG. 24 is a diagram describing related technology.

PREFERRED MODES

First, an outline of an exemplary embodiment of the present disclosureis described. FIG. 1 is a diagram showing a configuration of acommunication network and a configuration of a terminal 1. FIG. 2 is adiagram showing a configuration of a forwarding node 2 and a controldevice 3. It is to be noted that reference symbols attached to thedrawings are added for convenience to respective elements as an examplein order to aid understanding. The reference symbols are not intended tolimit the disclosure to modes of the drawings as illustrated.

On receiving a packet, the forwarding node 2 processes the packet inaccordance with a processing rule corresponding to the packet. Theprocessing rule specifies processing content for the packet. An exampleof a configuration of a processing rule is shown in FIG. 3. Theprocessing rule, for example, includes a matching rule for matching apacket and the processing rule, and processing content for the packetthat matches the processing rule. On receiving the packet, a processingunit 23 searches for a processing rule corresponding to the packet froma storage unit 21. That is, the processing unit 23 performs search in atable of a configuration exemplified in FIG. 3, which is stored in thestorage unit 21. For example, if the packet belongs to a “flow A”, itmatches a matching rule for “flow A”. It is to be noted that a “flow” isa sequence of packets identified in accordance with packet content(information such as packet source and destination, a combination ofplural information items included in the packet and/or the like). In acase of a processing rule corresponding to a packet being stored in thestorage unit 21, the processing unit 23 processes the packet inaccordance with the retrieved processing rule. For example, in anexample in FIG. 3, if a packet belongs to the “flow A”, the processingunit 23 executes processing content of “forward from port ‘a’ offorwarding node”. In a case where a processing rule corresponding to apacket is not stored in the storage unit 21, a control devicecommunication unit 22 transmits a request to set a processing rule, withrespect to the control device 3.

The control device 3 controls packet processing by the forwarding node2. When a communication unit 31 receives a request to set a processingrule from a forwarding node 2, a control unit 32 determines a processingrule corresponding to the setting request. The communication unit 31transmits the processing rule determined by the control unit 32 to theforwarding node 2. The processing rule specifies processing content fora packet such as, for example, packet transmission from a specifiedport, flooding, dropping, packet header rewriting, and the like.

The control device 3 sets processing rules not only for the forwardingnode 2, but also for a terminal 1 that communicates with a communicationnetwork including forwarding nodes 2 and the control device 3.Furthermore, the terminal 1 executes packet processing in accordancewith a set processing rule.

The terminal 1 transmits an access request to the communication networkvia a communication unit 10. It is to be noted that the terminal 1 is acommunication terminal such as a personal computer, a handheld device,or the like. The terminal 1 may have either a wired or wireless way ofcommunication.

On detecting an access request from the terminal 1, the forwarding node2 forwards the access request to the control device 3. For example, thecontrol device 3 sets in advance a processing rule corresponding to apacket for requesting access (for example, an authentication packet or alogin packet) to the storage unit 21 of the forwarding node 2. As shownin an example in FIG. 3, the control device 3 sets a processing rule inwhich a matching rule is “access request packet”, and correspondingprocessing content is “forwarding to control device”. The processingrule corresponding to the access request packet specifies, for example,processing for forwarding the access request packet to the controldevice 3. On receiving the access request packet, the processing unit 23of the forwarding node 2 forwards the access request packet to thecontrol device 3, in accordance with the processing rule correspondingto the access request packet.

When the control device 3 receives the access request packet forwardedfrom the forwarding node 2, the control unit 32 of the control device 3refers to a policy management unit 33 and retrieves a policycorresponding to a user of the terminal. It is to be noted that thepolicy management unit 33 may store a policy that is set for each ofterminals. The control unit 32 determines a processing rule set in theterminal 1, based on the retrieved policy. The communication unit 31transmits the determined processing rule to the terminal 1. It is to benoted, for example, that the control device 3 may set a period ofvalidity for the determined processing rule and transmit this to theterminal 1. In a case where a period of validity is set, the processingrule set in the terminal 1 is deleted from the terminal 1 when theperiod of validity has lapsed. It is to be noted that FIG. 2 shows anexample where the policy management unit 33 is included in the controldevice 3, but the policy may be managed by a device other than thecontrol device 3.

Furthermore, the control device 3 may determine the processing rule setin the terminal 1 based on information managed by the control device 3,without referring to the policy management unit 33.

In addition, the control device 3, for example, may set a processingrule for a forwarding node corresponding to a processing rule for aterminal set in the terminal, in a forwarding node 2. For example, in acase where the terminal 1 executes a rewriting process for some packetsin accordance with a processing rule set in the terminal 1, the controlterminal 3 may set a processing rule that matches rewritten contentcontained within a packet, in the forwarding node 2.

In a case where the communication unit 10 of the terminal 1 receives aprocessing rule from the control device 3, the terminal 1 sets theprocessing rule in the storage unit 11. When the processing unit 12 ofthe terminal 1 transmits or receives a packet to or from a communicationnetwork, the processing unit 12 searches for a processing rulecorresponding to the transmitted or received packet, from the storageunit 11. In a case where a processing rule corresponding to thetransmitted or received packet is stored in the storage unit 11, theprocessing unit 12 processes the packet in accordance with theprocessing rule. The processing unit 12, for example, executesprocessing for rewriting some packets to be transmitted or received, orpacket dropping processing, in accordance with the processing rule. In acase where a processing rule corresponding to the transmitted orreceived packet is not stored in the storage unit 11, the processingunit 12 may transmit or receive the packet without executing processingcorresponding to the packet, or may perform packet dropping. However,packet processing in a case where a processing rule corresponding to thetransmitted or received packet is not stored in the storage unit 11, isnot limited to this.

Next, a description is given of operations of the terminal 1 and thecontrol device 3, making reference to FIG. 4 and FIG. 5. FIG. 4 is aflowchart showing an example of operations of the terminal 1. In a caseof receiving a processing rule from the control device 3 (S1), theterminal 1 stores the received processing rule in the storage unit 11(S2).

In a case of packet transmission or reception with respect to thecommunication network (Yes in S3), the terminal 1 retrieves a processingrule corresponding to the transmitted or received packet (S4).

In a case of a processing rule corresponding to the transmitted orreceived packet being stored in the storage unit 11, the terminal 1processes the transmitted or received packet in accordance with theprocessing rule (S5).

FIG. 5 is a flowchart showing an example of operations of the controldevice 3. On receiving an access request from the terminal 1 (S6), thecontrol device 3 retrieves a policy corresponding to a user of theterminal, from the policy management unit 33 (S7). The access request istransmitted by a request transmitting function of the communication unit10.

The control device 3 determines a processing rule to be set in theterminal 1 based on the retrieved policy (S8), and transmits to theterminal 1 (S9).

The control device 3 sets the processing rule with regard to theterminal 1, and the terminal 1 itself executes packet processingcorresponding to the processing rule. Since the terminal 1 executespacket processing such as rewriting of some packets according to theprocessing rule, instead of the forwarding node 2, packet processingload on the forwarding node 2 is greatly reduced. Furthermore, since thecontrol device 3 can set a processing rule corresponding to content of aprocessing rule for a terminal set for the terminal 1, in advance in theforwarding node 2, it is possible to curtail requests to the controldevice 3 generated due to the processing rule not being set in theforwarding node 2. Therefore, the processing load on the control device3 is greatly reduced.

First Exemplary Embodiment

Next, a description is given concerning an outline of a first exemplaryembodiment of the present disclosure, making reference to the drawings.FIG. 6 shows an example of a system configuration in the first exemplaryembodiment. Referring to FIG. 6, the configuration is shown to include auser terminal 100, a plurality of forwarding nodes 200, a policymanagement device 300, and a control device 400.

The plurality of forwarding nodes 200 carry out processing of packetstransmitted from the user terminal, in accordance with a processing ruleset by the control device 400.

A terminal control device 110 inside the user terminal 100 storesprocessing rules set by the control device 400, and controls packet(s)transmitted by the user terminal based on a processing rule.

More specifically, the terminal control device 110 is provided with aprocessing rule storage unit 120 that stores processing rules todetermine whether or not to forward a packet transmitted from aprocessing rule determination unit 420, and an access control unit 130for allowing or denying access transmitted from the user terminal, basedon a processing rule stored in the processing rule storage unit 120.That is, the access control unit 130 confirms whether or not aprocessing rule corresponding to a packet transmitted from the terminal100 is stored in the processing rule storage unit 120. In a case where aprocessing rule corresponding to the packet transmitted from theterminal 100 is stored therein, the access control unit 130 confirmsprocessing content specified in the processing rule. In a case where theprocessing content denies forwarding of the packet, the access controlunit 130 does not forward the packet to a communication networkconfigured by the forwarding nodes 200, but executes an accessrestriction such as dropping the packet or the like.

The policy management device 300 manages the communication policy andnotifies the communication policy assigned to a user for whomauthentication has succeeded, to the control device 400.

More specifically, the policy management device 300 includes acommunication policy storage unit 310 that associates a role assigned tothe user and access rights set for each role. The policy managementdevice 300 provides information concerning the access rightscorresponding to the role of the user for whom authentication hassucceeded, to the control device 400, based on a result of userauthentication.

The control device 400 sets a processing rule specifying processingcontent of a packet, with respect to the forwarding node(s) 200. It isto be noted that reference symbols attached to the drawings are addedfor convenience to respective elements as an example in order to aidunderstanding. The reference symbols are not intended to limit thedisclosure to modes of the drawings as illustrated.

More specifically, the control device 400 determines a path between theterminal 100 of the user for whom authentication has succeeded, and anetwork resource 500 which the user can access, based on informationconcerning access rights received from the policy management device 300.The control device 400 includes a path control unit 410 that sets aprocessing rule in a forwarding node 200 in a determined path. Withregard to the processing rule set by the path control unit 410 in theforwarding node 200, the control device 400 is provided with aprocessing rule determination unit 420 that transmits a processing ruledetermining whether or not to forward a packet from the terminal 100, tothe terminal control device 110 of the user terminal 100.

The control device 400 may set a period of validity for a processingrule transmitted to the user terminal 100. In this case, the terminal100 deletes the processing rule for which the period of validity haslapsed. It is to be noted that in a case where the processing ruledetermination unit 420 transmits a processing rule denying packetforwarding from the terminal 100, the path control unit 410 need not seta processing rule corresponding to a determined path, with regard to theforwarding node(s) 200.

By setting the processing rule as described above, it is possible todetermine the accessible network resource 500, in accordance with therole assigned to the user, and furthermore, it is possible to set a pathto give access for each flow. In addition, by setting the abovementionedprocessing rule, it is possible to execute an access restriction in theuser terminal 100, with regard to a flow for which access by the user isdenied, among packet flows transmitted by the user.

Therefore, since the packet for which access is restricted has theaccess restricted by the terminal 100 without being transmitted to aforwarding node 200, processing load in the forwarding node 200 isreduced. Since by access restriction by the terminal 100 there is adecrease in packets sent at the occasion of a request to set aprocessing rule to be transmitted to the control device from theforwarding node 200, the load on the control device is greatly reduced.

It is to be noted that in a case where a period of validity is providedin the processing rule, and the period of validity has elapsed from asetting being performed in the forwarding node 200 and the accesscontrol unit 130 of the user terminal 100, or from a packet matching amatching rule finally being received, the processing rule that deniesforwarding of the packet may be deleted.

FIG. 7 is a diagram representing an example in which an access controlsystem is realized using the configuration of FIG. 6. The configurationshown in FIG. 7 is an example of the system, and the present disclosureis not limited to the system configuration disclosed in FIG. 7.Referring to FIG. 7, the configuration shown includes: a plurality ofthe forwarding nodes 200, a terminal control device 110 for controllingwhether or not to transmit a packet transmitted from the user terminal100, a control device 400 for setting processing rules in the forwardingnodes 200 and the terminal control device 110, a policy managementdevice 300 for notifying a communication policy to the control device400, and an authentication device 330 for providing authenticationinformation indicating an authentication result to the policy managementdevice 300.

A forwarding node 200 processes a received packet in accordance with aprocessing rule that associates a matching rule matching the receivedpacket and processing content to be applied to a packet that matcheswith the matching rule. For this type of forwarding node 200, anOpenFlow switch as disclosed in Non-Patent Literature 2 may be used.However, the forwarding node 200 is not limited to the OpenFlow switch.

A certain forwarding node 200 among the plurality of forwarding nodes200 is connected to network resources 500A and 500B. It is to be notedthat the network configuration shown in FIG. 7 is merely an example, andthe connection configuration of the forwarding node 200 and the networkresources 500A and 500B is not limited to the example of FIG. 7.

The user terminal 100 communicates with the network resources 500A and500B, via the forwarding nodes 200. In the example of FIG. 7, adescription is given in which the network resource 500A and the networkresource 500B each belong to different resource groups, and they arerespectively given resource group IDs of resource_group_0001 andresource_group_0002.

The authentication device 330 is an authentication server that uses apassword or biometric authentication or the like to perform a userauthentication procedure with the user terminal 100. The authenticationdevice 330 transmits authentication information indicating a result ofthe user authentication procedure with the user terminal 100 to thepolicy management device 300.

FIG. 8 is an example of authentication information held in theauthentication device 330 of the present exemplary embodiment. Forexample, in a case where the authentication of a user having a user IDof user1 succeeds, the authentication device 330 transmits an entry foruser1 including user ID: user1, attributes of IP address: 192.168.100.1,and MAC address: 00-00-00-44-55-66, and role IDs: role_0001 androle_0002, as authentication information to the policy management device300. In the same way, in a case where the authentication of a userhaving a user ID of user2 succeeds, the authentication device 330transmits an entry for user2 including user ID: user2, attributes of IPaddress: 192.168.100.2, and MAC address: 00-00-00-77-88-99, and Role ID:role_0002, as authentication information to the policy management device300.

The authentication information may be information by which the policymanagement device 300 can determine a communication policy assigned to auser, and there is no limitation to the example of FIG. 8. For example,the authentication information may be the user ID of a user for whomauthentication has succeeded, an access ID such as a role ID or MACaddress derived from the user ID in question, location information ofthe user terminal 100, or a combination of these. The authenticationdevice 330 may transmit information of a user for whom authenticationhas failed, as authentication information to the policy managementdevice 300, and may transmit a communication policy by which the policymanagement device 300 restricts access from the user in question, to thecontrol device 400.

The policy management device 300 is connected to the communicationpolicy storage unit 310 and a resource information storage unit 320,determines a communication policy corresponding to the authenticationinformation received from the authentication device 330, and transmitsthe determined communication policy to the control device 400.

FIG. 9 is an example of communication policy information stored in thecommunication policy storage unit 310. In the example of FIG. 9, thecommunication policy information has a resource group ID given to agroup of resources, and access rights, for each role identified by arole ID. For example, a user having the role ID: role_0001 is allowedaccess to both resource groups having IDs: resource_group_0001 andresource_group_0002. On the other hand, a user having the role ID:role_0002 is denied access to the resource group ID:resource_group_0001, but is allowed access to resource_group_0002.

FIG. 10 is an example of resource information stored in the resourceinformation storage unit 320. In the example of FIG. 10, the resourceinformation is information associated with a resource ID of a resourcebelonging to a resource group ID or other detailed attributes thereof(resource attributes). For example, with regard to the resourceinformation, resources having resource_0001, resource_0002, andresource_0003 are included in a group identified by the resource groupID: resource_group_0001, and port numbers used in respective IPaddresses, MAC addresses, and services thereof are included.

The policy management device 300 makes reference to the communicationpolicy information and the resource information, determines acommunication policy of a user who has received authentication by theauthentication device 330, and notifies the control device 400. Forexample, based on a role ID included in authentication informationreceived from the authentication device 330, the policy managementdevice 300 identifies content of a resource group ID and access rightsthereof attached to the role ID in question from the policy informationof FIG. 9. The policy management device 300 identifies the resourceinformation belonging to the resource group ID from the resourceinformation of FIG. 10. The policy management device 300 creates acommunication policy using the identified policy information and theresource information.

FIG. 11 shows an example of a communication policy of a user having auser ID: user1, created from information shown in FIG. 8, FIG. 9, andFIG. 10. Values of attribute information of the user ID: user1 of theauthentication information of FIG. 8 are set in a source field of FIG.11. Furthermore, resource attributes extracted from resource informationof FIG. 10 based on content of the role ID: role_0001 of the policyinformation of FIG. 9 are set in a destination field. Rights based onaccess rights of the role ID: role_0001 of the policy information ofFIG. 9 are set in an access rights field. In addition, content (forexample, service and port number) that has been set in a resourceattribute field of the resource information of FIG. 10 is set in acondition (option) field.

On receiving the communication policy, the control device 400 creates aprocessing rule specifying processing content to transmit to aforwarding node a request to set a processing rule for a packet from theuser to whom the communication policy in question is applied, and setsthe processing rule in at least one forwarding node among the pluralityof forwarding nodes 200. On receiving a packet from the user to whom thecommunication policy is applied, the forwarding node 200 transmits arequest to set a processing rule to the control device 400, based on theprocessing rule. On receiving the request to set the processing rule fora packet from the user to whom the communication policy is applied, thecontrol device 400 determines a forwarding path of the packet and aprocessing rule corresponding to the forwarding path, based on packetinformation included in the setting request, and sets the processingrule in the forwarding node 200 in the forwarding path of the packet inquestion. With regard to the processing rule set in the forwarding node,the control device 400 transmits a processing rule determining whetheror not to forward a packet from the terminal 100, to the terminalcontrol device 110 of the user terminal 100.

FIG. 12 is a block diagram representing a detailed configuration of thecontrol device 400. The control device 400 is provided with a nodecommunication unit 40 that performs communication with a forwardingnode(s) 200, a control message processing unit 41, a processing rulemanagement unit 42, a processing rule storage unit 43, a forwarding nodemanagement unit 44, a path-action calculation unit 45, a topologymanagement unit 46, a terminal location management unit 47, acommunication policy management unit 48, and a communication policystorage unit 49.

The control message processing unit 41 analyzes a control messagereceived from the forwarding node 200 and delivers the control messageinformation to a corresponding functional block inside the controldevice 400, in accordance with a result of the analysis.

The processing rule management unit 42 manages what a processing rule,and in which forwarding node 200 is set. Specifically, a processing rulecreated by the path-action calculation unit 45 is registered in theprocessing rule storage unit 43 and set in the forwarding node 200, andupdating is performed of registration information of the processing rulestorage unit 43 in response to a case where a change occurs in theprocessing rules set in the forwarding node 200, according to aprocessing rule deletion notice from the forwarding node 200.

The forwarding node management unit 44 manages the capability (forexample, number and type of ports, type of processing content supported,and the like) of the forwarding node(s) 200 controlled by the controldevice 400.

On receiving a communication policy from the communication policymanagement unit 48, the path-action calculation unit 45 creates aprocessing rule to execute a request to set a processing rule withrespect to a packet transmitted from a terminal used by the user inquestion, in accordance with the communication policy concerned. It isto be noted that the forwarding node(s) 200 that is a set destination ofthe created processing rule may be all (or any) of the forwarding nodes200 to which the user terminal 100 can connect, or may be a selection ofany forwarding node 200 based on source information included in thecommunication policy.

On receiving a request to set a processing rule with respect to a packettransmitted from the terminal used by the user, the path-actioncalculation unit 45 determines a forwarding path of the packet inquestion and a processing rule corresponding to the forwarding path inquestion, based on packet information included in the request.

Furthermore, the path-action calculation unit 45 calculates the packetforwarding path based on network topology information built by thetopology management unit 46. It is to be noted that the path-actioncalculation unit 45 may calculate the forwarding path of the packetgiving consideration also to location information of the communicationterminal managed by the terminal location management unit 47. Next, thepath-action calculation unit 45 acquires port information and the likeof the forwarding nodes 200 in the forwarding path from the forwardingnode management unit 44, and obtains processing content to be executedby the forwarding node(s) 200 in the path, and a matching rule foridentifying flow to which the processing content is applied. It is to benoted that the matching rule can be created using the source IP address,the destination address, a condition (option) and the like, of thecommunication policy of FIG. 11. Accordingly, in a case of the firstentry of the communication policy of FIG. 11, with respect to thepath-action calculation unit 45, a processing rule is created thatspecifies processing content and the like, for forwarding a packet froma source IP address of 192.168.100.1 to a destination of IP 192.168.0.1,from a prescribed port of the forwarding node 200. It is to be notedthat the path-action calculation unit 45, when setting a processingrule, may create not only a packet for which a request is received toset a processing rule, but may also create a processing rule realizingpacket forwarding to a resource to which the user terminal has accessrights.

The topology management unit 46 builds network topology informationbased on connection relationships of forwarding nodes 200 collected viathe node communication unit 40.

The terminal location management unit 47 manages information foridentifying the location of the user terminal connected to thecommunication system. In the present exemplary embodiment, a descriptionis given in which the IP address is used as information for identifyingthe user terminal, and a forwarding node identifier of a forwarding nodeto which the user terminal is connected and information of a portthereof are used as information for identifying the location of the userterminal. However, information for identifying the user terminal and thelocation of the user terminal is not limited to this. For example, aterminal and its location may be identified by using informationprovided by the authentication device 330.

On receiving communication policy information from the policy managementdevice 300, the communication policy management unit 48 stores theinformation in the communication policy storage unit 49, and alsotransmits the information to the path-action calculation unit 45.

It is to be noted that the OpenFlow controller of Non-Patent Literatures1 and 2 may be applied as the control device 400. That is, operationalfunctions of a processing rule (flow entry) on the occasion of receivingthe communication policy may be added to the OpenFlow controller.

The processing rule determination unit 420 transmits to the processingrule storage unit 120 of the terminal control device 110 a processingrule for determining whether or not to forward a packet, (for example, aprocessing rule with a source of “192.168.100.1”, a destination of“192.168.0.3”, and access rights of “deny” in the table of FIG. 11)among processing rules created by the path-action calculation unit 45. Amethod of forwarding from the control device 400 to the processing rulestorage unit 120 of the terminal control device 110 may be by a wiredconnection, a wireless connection, or any other forwarding method.

Each unit (processing means) of the control device 400 shown in FIG. 12,and the path control unit 410 and the processing rule determination unit420 can be realized by a computer program that stores the abovementionedrespective information and executes the respective processes describedabove in a computer configuring the control device 400, using hardwarethereof.

The terminal control device 110 in FIG. 7 is configured from theprocessing rule storage unit 120 and the access control unit 130,similar to FIG. 6. The processing rule storage unit 120 receives andstores a processing rule for determining whether or not to forward apacket, from the control device 400. The access control unit 130executes access control for a packet transmitted from the user terminal100, in accordance with a processing rule recorded in the processingrule storage unit 120. That is, in a case where denial of access isspecified in a processing rule corresponding to a packet transmitted bythe user terminal 100, the access control unit 130 restrictstransmission of the packet in question.

The processing rule storage unit 120 and the access control unit 130 ofthe abovementioned terminal control device 110 can be realized by acomputer program that stores the abovementioned respective informationand executes the respective processes described above in a computer ofthe user terminal that configures the terminal control device 110, usinghardware thereof.

Next a detailed description is given concerning operations of thepresent exemplary embodiment, making reference to the drawings. FIG. 13,FIG. 14, and FIG. 15 are sequence diagrams representing a sequence ofoperations of the present exemplary embodiment. Referring to FIG. 13,when the user terminal makes a login request (access request) to theauthentication device 330, a packet corresponding to the login requestis forwarded to the authentication device 330 (S001 in FIG. 13).

The authentication device 330 performs user authentication (S002 in FIG.13). The authentication device 330 transmits authentication informationto the policy management device 300 (S003 in FIG. 13). The policymanagement device 300 refers to the communication policy storage unit310 and the resource information storage unit 320, based on the receivedauthentication information, and determines a communication policy (S004in FIG. 13). The policy management device 300 transmits the determinedcommunication policy to the control device 400 (S005 in FIG. 13).

On receiving the communication policy, the control device 400 sets, in aforwarding node 200, a processing rule specifying processing content inwhich a request to set a processing rule corresponding to the packettransmitted from the user terminal is created and transmitted to thecontrol device 400 (S006 in FIG. 13). The control device 400, based onthe communication policy, determines whether or not to forward thepacket and creates a processing rule corresponding to a result of thedetermination (S007 in FIG. 13). The control device 400 transmits thecreated processing rule to the terminal control device 110 (S008 in FIG.13).

On receiving the processing rule transmitted by the control device 400,the terminal control device 110 registers the processing rule in theprocessing rule storage unit 120 (S009 in FIG. 13).

A description is given concerning operations in a case where forwardingof the packet from the user terminal is allowed, and a case wheretransmission of the packet is denied, using FIG. 14 and FIG. 15,respectively.

FIG. 14 is a sequence diagram representing a sequence of operations in acase where transmission of the packet by the terminal control device 110is allowed. The user terminal transmits the packet with a destination ofa network resource (S101 in FIG. 14). The terminal control device 110receives the packet and determines whether or not to transmit the packetto the network resource (S102 in FIG. 14). The terminal control device110 compares the destination IP address of the packet transmitted fromthe user terminal and processing rules registered in the processing rulestorage unit 120. In a case where it is specified that access isallowed, in a processing rule corresponding to the packet transmittedfrom the user terminal, the terminal control device 110 transmits thepacket to the forwarding node 200 (S103 in FIG. 14).

The forwarding node 200 receives the packet from the terminal controldevice 110, determines a forwarding path of the packet in accordancewith the processing rule registered by the control device 400 (S104 inFIG. 14), and forwards the packet to the network resource (S105 in FIG.14).

FIG. 15 is a sequence diagram representing a sequence of operations in acase where transmission of a packet by the terminal control device 110is denied. When the user terminal transmits the packet with adestination of a network resource (S201 in FIG. 15), the terminalcontrol device 110 receives the packet and determines whether or not totransmit the packet to the network resource (S202 in FIG. 15). Theterminal control device 110 compares the destination IP address of thepacket transmitted from the user terminal and processing rulesregistered in the processing rule storage unit 120. In a case wherecontent is specified showing that access is denied, in a processing rulecorresponding to the packet transmitted from the user terminal, theterminal control device 110 restricts transmission of the packet (thepacket is dropped or the like) (S203 in FIG. 15).

It is to be noted that the control device 400 may set the processingrule for the terminal, or the terminal may periodically refer to thecontrol device 400 and the terminal may obtain the processing rule.Furthermore, a combination of the two mechanisms is also possible.

The mechanism for allowing or denying forwarding of a packet by theaccess control unit 130 may be a mechanism similar to a method performedin a forwarding node, or may use packet filtering technology as iniptables. Furthermore, the access control unit 130 of the terminalcontrol device 110 can also apply a processing rule allowing or denyingforwarding of a packet with respect to a physical NIC (Network InterfaceCard) inside the user terminal; application is also possible torespective virtual NICs held by plural VMs (Virtual Machines) operatinginside the user terminal; and application is also possible to aplurality of virtual switches operating inside the user terminal. Inthis way, the access control unit 130 can freely specify a place (orsection) for executing access control inside the user terminal.

As described above, the packet transmitted from the user terminal can besubjected to access restriction inside the user terminal, without beingtransmitted to the forwarding node 200, by the terminal control device110 inside the user terminal. Therefore, the load on a control deviceaccompanying a request to set a processing rule and the load offorwarding processing of a forwarding node can be greatly reduced.

Second Exemplary Embodiment

Next, a description is given concerning a second exemplary embodiment ofthe present disclosure, in which a modification is added to operationsof the policy management device of the first exemplary embodimentdescribed above. Since the present exemplary embodiment can beimplemented by a configuration equivalent to the first exemplaryembodiment described above, a description is given below centered onpoints of difference in operation thereof.

FIG. 16 is a sequence diagram representing a sequence of operations ofthe second exemplary embodiment of the present disclosure. A userterminal makes a login request to an authentication device 330 (S301 inFIG. 16). The authentication device 330 performs user authentication(S302 in FIG. 16). The authentication device 330 transmitsauthentication information to a policy management device 300 based on aresult of user authentication (S303 in FIG. 16).

A policy management device 300 determines a communication policy for auser based on the authentication information received from theauthentication device 330 (S304 of FIG. 16). The policy managementdevice 300 transmits the determined communication policy to the controldevice 400 (S305 in FIG. 16).

The control device 400 creates a processing rule based on thecommunication policy received from the policy management device 300, andsets the processing rule in a forwarding node 200 (S306 in FIG. 16).These operations are the same as the first exemplary embodiment. In thepresent exemplary embodiment, after the control device 400 has set theprocessing rule in the forwarding node 200, reference is made to contentof the processing rule, and the processing rule for determining whetheror not to forward a packet is created and transmitted to the policymanagement device 300 (S307, 308 in FIG. 16).

The policy management device 300 that has received the processing rulefor determining whether or not to forward a packet uses information of acommunication policy storage unit 310 and a resource information storageunit 320 to select another user for whom the processing rule is to beapplied (S309 in FIG. 16).

FIG. 17 is a diagram representing an example in which the policymanagement device 300, which has received the processing rule fordetermining whether or not to forward a packet, selects another user forwhom the processing rule is to be applied. For example, referring toFIG. 17, there is a processing rule (below, a processing rule (a)) thatdenies access where a source is “IP: 192.168.100.0/24” and a destinationis “192.168.0.3”. In this case, the policy management device 300searches for another user (resource ID or resource group ID) matchingthe processing rule (a), and selects another user who matches (forexample, with a source of “192.168.100.10”, and other conditions havingthe same resource ID and resource group ID as for the user of theprocessing rule (a)). In the description below, a user who performslogin processing (S301) of FIG. 16 is A, a user terminal used by user Ais a user terminal A, and a terminal control device possessed by theuser terminal A is terminal control device A. Furthermore, a userselected based on a processing rule received from the control device 400by the policy management device 300 of FIG. 16 is B, a user terminalused by user B is a user terminal B, and a terminal control devicepossessed by the user terminal B is terminal control device B.

The policy management device 300 receives the processing rule (a) fordetermining whether or not to forward a packet to user A from thecontrol device 400, and after selecting user B who matches theprocessing rule (a), sets respective processing rules in the terminalcontrol device A of the user terminal A, and the terminal control deviceB of the user terminal B (S310 and S312 of FIG. 16). It is to be notedthat any order may be used as the order in which the control device 400transmits the processing rules to the terminal control device A and theterminal control device B.

On receiving the processing rule transmitted by the control device 400,the terminal control device A registers the processing rule in aprocessing rule storage unit of the terminal control device A (S311 inFIG. 16). Similarly, on receiving the processing rule transmitted by thecontrol device 400, the terminal control device B registers theprocessing rule in a processing rule storage unit of the terminalcontrol device B (S313 in FIG. 16).

Thereafter, operations in a case where packet transmission from the userterminal A and the user terminal B is allowed, and in a case wherepacket transmission is denied, are similar to the first exemplaryembodiment described using FIG. 14 and FIG. 15.

As a result of the above sequence of operations, in a case where aprocessing rule set for a certain user's terminal is also applicable toanother user, by registering the processing rule in advance in theterminal control device of the other user also, it is possible to reducethe load of the control device accompanying the request to set aprocessing rule and the load of forwarding processing of a forwardingnode.

Third Exemplary Embodiment

Next, a description is given of a third exemplary embodiment of thepresent disclosure, making reference to FIG. 18. Where respectiveelements in FIG. 18 have the same reference numbers as elements in otherexemplary embodiments, the elements are the same as content described inthe other exemplary embodiments. Below, in the present exemplaryembodiment, a detailed configurational description is omitted.

A control device 400 sets a processing rule specifying writing of anidentifier of a terminal to a packet, with respect to a terminal 100. Itis to be noted that occasions at which the processing rule is set forthe terminal 100 by the control device 400 may be arbitrary. Forexample, in a case where the control device 400 receives a packet (forexample, an authentication packet or a login packet) for requestingaccess, transmitted by the terminal 100, a processing rule may be setfor the terminal 100. Furthermore, the control device 400 may set aprocessing rule for the terminal 100 at arbitrary timing.

The control device 400 includes in the processing rule a matching rulefor matching a packet that is a target of processing to write theidentifier of the terminal, and sets the processing rule in the terminal100.

The terminal 100 writes the identifier in the terminal in an arbitraryfield of the packet (for example, a prescribed field of a header), inaccordance with the set processing rule. The terminal 100 transmits thepacket in which the identifier is written to a network configured offorwarding nodes 200.

A forwarding node 200 receives the packet including the identifier ofthe terminal from the terminal 100, and checks whether or not there is aprocessing rule corresponding to the identifier of the terminal, fromprocessing rules it holds. In a case where there is no processing rulecorresponding to the identifier of the terminal, the forwarding node 200transmits a request to set a processing rule corresponding to theidentifier of the terminal, to the control device 400.

The control device 400 that receives the request from the forwardingnode 200 determines a forwarding path corresponding to the identifier ofthe terminal, and transmits a processing rule corresponding to theforwarding path to the forwarding node(s) 200. In the processing ruleset in the forwarding node 200, the identifier of the terminal is set ina matching rule, and processing of a packet corresponding to theidentifier is set in processing content. After the processing rule hasbeen set, the forwarding node(s) 200 concerned processes the packet thatincludes the identifier of the terminal, in accordance with a processingrule matching the identifier of the terminal included in the packet.

According to the present exemplary embodiment, the control device 400can flexibly control packet flow in terminal units. Furthermore, sincethere is no necessity for the control device 400 or the forwardingnode(s) 200 to recognize the identifier of the terminal, the processingload necessary for collecting terminal identifiers by the control device400 and the forwarding node 200 is greatly reduced. In addition, sincethe processing device 400 can set a processing rule that corresponds toan identifier of a terminal in advance in the forwarding node 200, it ispossible to curtail requests to the control device 400 generated due tothe processing rule not being set in the forwarding node 200. Therefore,the processing load on the control device 400 is greatly reduced.

Fourth Exemplary Embodiment

Next, a description is given of a fourth exemplary embodiment of thepresent disclosure, making reference to FIG. 19. Where respectiveelements in FIG. 19 have the same reference numbers as elements in otherexemplary embodiments, the elements are the same as content described inthe other exemplary embodiments. Below, in the present exemplaryembodiment, a detailed configurational description is omitted.

A control device 400 sets a processing rule concerning QoS with regardto a prescribed terminal 100. It is to be noted that occasions at whicha processing rule is set for the terminal 100 by the control device 400may be arbitrary. For example, in a case where the control device 400receives a packet (for example, an authentication packet or a loginpacket) for requesting access, transmitted by the terminal 100, aprocessing rule may be set for (or to) the terminal 100. Furthermore,the control device 400 may set a processing rule for the terminal 100 atarbitrary timing. In addition, the control device 400 may transmit QoSinformation to only a prescribed terminal 100 selected by a prescribedcondition.

The processing rule concerning QoS, for example, specifies processingfor writing QoS information of a packet to a packet that has beentransmitted from the prescribed terminal 100. It is to be noted that theQoS information is, for example, a QoS class in which class division isdone according to a priority. The control device 400 controls aforwarding node 200 so as to accommodate a band, with regard to a packetwith a high QoS class. Furthermore, the control device 400 may set aprocessing rule specifying writing of a low QoS class to a packet, forthe terminal 100, and may control the forwarding node 200 so as totemporarily isolate traffic from a heavy user with high frequency ofcommunication, in a path with a narrow band. The control device 400 maydetermine the processing rule set in the terminal 100 based oncommunication records or location information of the terminal 100.

The control device 400 includes in the processing rule a matching rulefor matching a packet that is a target for processing to write the QoSinformation, and sets the processing rule in the terminal 100.

The terminal 100 writes the QoS information in an arbitrary field of thepacket (for example, a prescribed field of a header), in accordance withthe set processing rule. The terminal 100 transmits the packet in whichthe QoS information is written to a network configured of forwardingnodes 200.

A forwarding node 200 receives the packet including the QoS informationfrom the terminal 100, and checks whether or not there is a processingrule corresponding to the QoS information, from processing rules itholds. In a case where there is no processing rule corresponding to theQoS information, the forwarding node 200 transmits a request to set aprocessing rule corresponding to the QoS information included in thepacket to the control device 400. However, the control device 400 mayset a processing rule corresponding to the QoS information in advance inthe forwarding node 200. In this case, requests to set a processing rulewith respect to the control device 400 are greatly reduced.

The control device 400 that receives the request from the forwardingnode 200 determines a forwarding path corresponding to the QoSinformation, and transmits a processing rule corresponding to theforwarding path to the forwarding node 200. In the processing rule setin the forwarding node 200, the QoS information is set in a matchingrule, and processing of a packet corresponding to the QoS information isset as processing content. After the processing rule has been set, theforwarding node 200 processes the packet that includes the QoSinformation in accordance with a processing rule matching the QoSinformation included in the packet.

According to the present exemplary embodiment, it is possible to executeQoS control for a terminal by the initiative of a network operator whoadministers the control device 400. Furthermore, since the controldevice 400 can set a processing rule corresponding to the QoSinformation in advance in the forwarding node 200, it is possible togreatly reduce requests to set processing rules from the forwardingnodes 200. Therefore, the processing load on the control device 400 isgreatly reduced. Furthermore, since there is no necessity to executeprocessing to write the QoS information in the forwarding nodes 200, itis possible to greatly reduce the load of packet processing with regardto the forwarding nodes 200.

Fifth Exemplary Embodiment

Next, a description is given of a fifth exemplary embodiment of thepresent disclosure, making reference to FIG. 20. Where respectiveelements in FIG. 20 have the same reference numbers as elements in otherexemplary embodiments, the elements are the same as content described inthe other exemplary embodiments. Below, in the present exemplaryembodiment, a detailed configurational description is omitted.

A control device 400 sets a processing rule for a prescribed terminal100, specifying redirection of an access request of the terminal 100. Ina case where it is desired to lead (guide) a user of the terminal 100 toa specific advertizing site for example, the control device 400 sets aprocessing rule specifying redirection of the access request. Forexample, in a case where the terminal 100 requests access to a certainsite carrying out e-commerce, the control device 400 sets a processingrule for the terminal 100 so as to redirect the access request to arelated site carrying out a special event such as a discount or thelike. It is to be noted that the control device 400 may set a processingrule for the terminal 100, so as to make a redirection only for thefirst access request of the terminal 100. The control device 400 may adda period of validity to the processing rule redirecting communication inthe terminal 100, and set the processing rule in the terminal 100.Furthermore, the control device 400 may refer to a communication recordof the terminal 100 to determine a redirection destination. For example,the control device 400 may analyze user preferences based on acommunication record, and may set a processing rule for the terminal100, redirecting to an advertizing site or the like, corresponding tothe preferences. Furthermore, the control device 400 may determine aredirection destination based on the location of the terminal 100. Thecontrol device 400 recognizes the location of the terminal 100 based onlocation information (GPS or the like) transmitted from the terminal100, for example, or location information of an access point at whichthe terminal 100 accesses a network. The control device 400 sets aprocessing rule specifying redirection to a destination of a prescribedwebsite or the like related to the location, based on the location ofthe terminal 100.

The control device 400, for example, transmits to the terminal 100 aprocessing rule executing rewriting of a “destination” field of a headerof an access request packet transmitted from the terminal 100.Furthermore, the control device 400 determines a forwarding pathcorresponding to the redirection destination, and sets a processing rulecorresponding to the determined path in a forwarding node 200. Thecontrol device 400 may set a processing rule corresponding to theredirection destination in advance in the forwarding node 200. In thiscase, requests to set processing rules with respect to the controldevice 400 are greatly reduced.

The control device 400 includes, in the processing rule, a matching rulefor matching a packet that is a target for redirection, and sets theprocessing rule in the terminal 100.

The terminal 100 rewrites the destination field of a packet header inaccordance with the processing rule that has been set, to a redirectiondestination set in the processing rule. The terminal 100 transmits thepacket in which the destination field has been rewritten to a networkconfigured of forwarding nodes 200.

The forwarding node(s) 200 forwards the packet in accordance with aprocessing rule corresponding to the redirection destination.

According to the present exemplary embodiment, by using the controldevice 400, a service provider in the network can lead the user of aterminal to a specific site. Furthermore, since the control device 400can set a processing rule corresponding to a redirected destination inadvance in the forwarding nodes 200, it is possible to greatly reducerequests to set processing rules from the forwarding nodes 200.Therefore, the processing load on the control device 400 is greatlyreduced. In addition, since there is no necessity to execute processingto rewrite the packet destination in the forwarding nodes 200, packetprocessing with regard to the forwarding nodes 200 is greatly reduced.

Sixth Exemplary Embodiment

Next, a description is given of a sixth exemplary embodiment of thepresent disclosure, making reference to FIG. 21. Where respectiveelements in FIG. 21 have the same reference numbers as elements in otherexemplary embodiments, the elements are the same as content described inthe other exemplary embodiments. Below, in the present exemplaryembodiment, a detailed configurational description is omitted.

A control device 400 sets a processing rule specifying writing ofbilling information for a terminal user to a packet, with respect to aprescribed terminal 100. The billing information, for example, relatesto a billing class whereby the terminal user makes a contract with anetwork operator in accordance with quality of communication service andthe like. It is to be noted that occasions at which a processing rule isset for the terminal 100 by the control device 400 may be arbitrary. Forexample, in a case where the control device 400 receives a packet (forexample, an authentication packet or a login packet) for requestingaccess, transmitted by the terminal 100, a processing rule may be setfor the terminal 100. Furthermore, the control device 400 may set aprocessing rule for the terminal 100 at arbitrary timing.

The control device 400 includes, in the processing rule, a matching rulefor matching a packet that is a target for processing to write thebilling information, and sets the processing rule in the terminal 100.

The control device 400 controls forwarding node(s) 200 so as to provide,for packets of a high billing class, a higher service quality (i.e.,giving priority to certain band range, or the like) than packets in alow billing class.

The terminal 100 writes the billing information in an arbitrary field ofthe packet (for example, a prescribed field of a header), in accordancewith the set processing rule. The terminal 100 transmits the packet inwhich the billing information is written to a network configured of theforwarding nodes 200.

A forwarding node 200 receives the packet including the billinginformation from the terminal 100 and checks whether or not there is aprocessing rule corresponding to the billing information, fromprocessing rules it holds. In a case where there is no processing rulecorresponding to the billing information, the forwarding node 200transmits a request to set a processing rule corresponding to thebilling information included in the packet to the control device 400.However, the control device 400 may set a processing rule correspondingto the billing information in advance in the forwarding node 200. Inthis case, requests to set a processing rule with respect to the controldevice 400 are greatly reduced.

The control device 400 that receives the request from the forwardingnode 200 determines a forwarding path corresponding to the billinginformation and transmits a processing rule corresponding to theforwarding path to the forwarding node 200. In the processing rule setin the forwarding node 200, the billing information is set in a matchingrule, and processing of a packet corresponding to the billinginformation is set as processing content. After the processing rule hasbeen set, the forwarding node 200 processes the packet that includes thebilling information in accordance with a processing rule matching thebilling information included in the packet.

It is to be noted that a combination of the present exemplary embodimentand the fifth exemplary embodiment is also possible. The control device400 may set a processing rule specifying redirection to a siterecommending an upgrade of the billing class, to a user terminal 100 forwhich the billing class is low and which is in a state withcommunication service quality below a prescribed threshold whichcontinues for a certain fixed period.

According to the present exemplary embodiment, it is possible to controlthe communication service quality in accordance with billing informationof a terminal user by the initiative of a network operator whoadministers the control device 400. Furthermore, since the controldevice 400 can set a processing rule corresponding to the billinginformation in advance in the forwarding node 200, it is possible togreatly reduce requests to set processing rules from the forwardingnodes 200. Therefore, the processing load on the control device 400 isgreatly reduced. Furthermore, since there is no necessity to executeprocessing to write the billing information in the forwarding nodes 200,it is possible to greatly reduce the load of packet processing withregard to the forwarding nodes 200.

Seventh Exemplary Embodiment

Next, a description is given concerning a seventh exemplary embodiment.FIG. 22 is a diagram representing an example of a configuration of theseventh exemplary embodiment of the present disclosure. The seventhexemplary embodiment differs from the exemplary embodiments describedabove in that a control device 400A includes an alteration judging unit610. The alteration judging unit 610 holds a hash value of a processingrule set in a terminal 100, determined by a processing ruledetermination unit 420.

The alteration judging unit 610 compares a hash value of a processingrule recorded in a processing rule storage unit 120 of a terminalcontrol device 110, and a (own) hash value that the alteration judgingunit itself holds. In a case where the hash values are different, thealteration judging unit 610 judges that the processing rule set in theterminal 100 has been altered. In order to ensure the security of acommunication system, the alteration judging unit 610 registers aprocessing rule denying access from that terminal 100, in forwardingnodes 200. It is to be noted that, when setting the processing ruledenying access in the forwarding nodes 200, the alteration judging unit610 may set a period of validity in the processing rule.

Next, a description is given concerning operation of the seventhexemplary embodiment. A description concerning operations that are thesame as the exemplary embodiment described above is omitted. Below, adescription is given centered on points of difference in operations.

FIG. 23 is a sequence diagram representing a sequence of operations ofthe seventh exemplary embodiment of the present disclosure. A userterminal makes a login request to an authentication device 330 (S401 inFIG. 23). The authentication device 330 performs user authentication(S402 in FIG. 23). The authentication device 330 transmitsauthentication information to a policy management device 300 based on aresult of user authentication (S403 in FIG. 23).

The policy management device 300 determines a communication policy for auser based on the authentication information received from theauthentication device 330 (S404 of FIG. 23). The policy managementdevice 300 transmits the determined communication policy to the controldevice 400 (S405 in FIG. 23).

The control device 400 determines a processing rule based on thecommunication policy received from the policy management device 300, andsets the processing rule in a forwarding node 200. On receiving thecommunication policy, the control device 400 sets a processing rule toperform a request to set a processing rule concerning a packet from auser terminal, in the forwarding node 200 (S406 in FIG. 23). The controldevice 400 determines a processing rule for setting in the terminal 100(S407 in FIG. 23). The control device 400 transmits the determinedprocessing rule to the terminal control device 110 (S408 in FIG. 23).

On receiving the processing rule transmitted by the control device 400,the terminal control device 110 registers the processing rule in theprocessing rule storage unit 120 (S409 in FIG. 23).

The alteration judging unit 610 of the control device 400 generates ahash value requested by a set processing rule with respect to theterminal 100 (S410 in FIG. 23).

The terminal control device 110 generates a hash value requested by theprocessing rule set by the control device 400 (S411 in FIG. 23), andtransmits the hash value to the alteration judging unit 610 of thecontrol device 400 (S412 in FIG. 23).

The alteration judging unit 610 of the control device 400 collates thehash value generated by the alteration judging unit 610 and the hashvalue transmitted by the terminal control device 110 (S413 in FIG. 23).If the result of the collation of the hash values is that the valuesmatch, the alteration judging unit 610 of the control device 400 regardsthis as normal, and completes the sequence of processes. On the otherhand, if the result of the collation of the hash values is that thevalues are different, a determination is made that a processing rule hasbeen altered by the user of the terminal 100, a processing rule denyingaccess from that terminal 100 is generated, and the processing rule isset in the forwarding node 200 (S414 in FIG. 23). It is to be noted thatthe alteration judging unit 610 may set a period of validity in theprocessing rule denying access from the terminal 100.

As a result of the above sequence of operations, in a case where acertain user has altered a processing rule held in the user terminal,the control device detects the alteration, and by setting a processingrule denying all access by that user in forwarding nodes, it is possibleto prevent the access control system in question from beingintentionally controlled by the user.

Descriptions of respective exemplary embodiments of the presentdisclosure have been given above, but the present disclosure is notlimited to the abovementioned exemplary embodiments, and it is possibleto add further modifications, substitutions, and adjustments within ascope that does not depart from fundamental technological concepts ofthe disclosure. For example, in the respective exemplary embodimentsdescribed above, a description has been given in which the controldevice 400, the authentication device 330, the policy management device300, the communication policy storage unit 310, and the resourceinformation storage unit 320 are each provided independently, but it isalso possible to employ a configuration in which at least some of theseare integrated as appropriate.

Furthermore, in the above exemplary embodiments a description has beengiven where access control is performed by assigning a role ID to auser, as shown in FIG. 8 to FIG. 11, but it is also possible to performaccess control by using an access ID such as a MAC address, or a user IDassigned to each user, or location information of the user terminal 100,or the like.

In addition, in the abovementioned exemplary embodiments a descriptionhas been given in which the user terminal 100 performs an authenticationprocedure with the authentication device 330 via a forwarding node 200,but it is also possible to employ a configuration in which the userterminal 100 communicates directly with the authentication device 330and implements the authentication procedure.

It is to be noted that each disclosures of the abovementioned PatentLiteratures and non-Patent Literatures are incorporated herein byreference thereto. Modifications and adjustments of exemplaryembodiments are possible within the bounds of the entire disclosure(including the scope of the claims) of the present invention, and alsobased on fundamental technological concepts thereof. Furthermore, a widevariety of combinations and selections of various disclosed elements(including description, exemplary embodiments, examples figures andclaims) is possible within the generic scope of the claims of thepresent invention. That is, the present invention clearly includes everytype of transformation and modification that a person skilled in the artcan realize according to the entire disclosure including the scope ofthe claims and to technological concepts thereof.

REFERENCE SIGNS LIST

-   1 terminal-   2 forwarding node-   3 control device-   10 communication unit-   11 storage unit-   12 processing unit-   21 storage unit-   22 control device communication unit-   23 processing unit-   31 communication unit-   32 control unit-   33 policy management unit-   40 node communication unit-   41 control message processing unit-   42 processing rule management unit-   43 processing rule storage unit-   44 forwarding node management unit-   45 path-action calculation unit-   46 topology management unit-   47 terminal location management unit-   48 communication policy management unit-   49 communication policy storage unit-   100 terminal-   110 terminal control device-   120 processing rule storage unit-   130 access control unit-   200 forwarding node-   300 policy management device-   310 communication policy storage unit-   320 resource information storage unit-   330 authentication device-   400, 400A control device-   410 path control unit-   420 processing rule determination unit-   500, 500A, 500B network resource-   610 alteration judging unit

1. A terminal, that communicates with a network including at least oneforwarding device for forwarding a packet, and a control device forcontrolling said forwarding device in accordance with a request fromsaid forwarding device, said terminal comprising: a communication unitthat receives a processing rule indicating that a packet forcommunicating with a first destination is changed so as to communicatewith a second destination, from said control device; a storage unit thatstores said received processing rule; and a processing unit that in acase of communicating with said network, changes a destination of apacket in accordance with a processing rule that corresponds to saidpacket by referring to said processing rule stored in said storage unit.2. The terminal according to claim 1, wherein said communication unitreceives a processing rule determined by said control device based on aprescribed condition.
 3. The terminal according to claim 1, wherein saidcommunication unit receives a processing rule determined by said controldevice based on a policy corresponding to a user of an own terminal. 4.The terminal according to claim 1, wherein said communication unitreceives a processing rule determined by said control device based on acommunication record of a user of an own terminal.
 5. The terminalaccording to claim 1, wherein said communication unit receives aprocessing rule determined by said control device based on informationrelated to the location of an own terminal.
 6. The terminal according toclaim 1, wherein said communication unit comprises a requesttransmission function that transmits an access request to said network,and wherein said communication unit receives a processing ruledetermined by said control device in accordance with said accessrequest.
 7. The terminal according to claim 1, wherein saidcommunication unit comprises a request transmission function thattransmits an access request to said network, and Wherein saidcommunication unit receives a processing rule determined by said controldevice in accordance with said access request transmitted via saidforwarding device.
 8. The terminal according to claim 1, wherein saidprocessing unit collates information included in a packet and aprocessing rule stored in said storage unit, and processes said packetin accordance with a processing rule corresponding to informationincluded in said packet.
 9. A control device, that sets a processingrule for a packet with respect to at least one forwarding device forforwarding packets, said control device comprising: a request receivingunit that receives an access request transmitted from a terminal foraccessing a network in which said forwarding device processes a packetin accordance with said processing rule; a control unit that generates aprocessing rule indicating that a packet for communicating with a firstdestination is changed so as to communicate with a second destination;and A communication unit that transmits said generated processing ruleto said terminal.
 10. The control device according to claim 9, whereinsaid control unit determines a processing rule based on a prescribedcondition.
 11. The control device according to claim 9, wherein saidcontrol unit determines a processing rule based on a policycorresponding to a user of said terminal.
 12. The control deviceaccording to claim 9, wherein said control unit determines a processingrule based on a communication record of said terminal.
 13. The controldevice according to claim 9, wherein said control unit determines aprocessing rule based on information related to location of saidterminal.
 14. The control device according to claim 9, wherein saidcontrol unit determines a processing rule in accordance with an accessrequest transmitted via said forwarding device.
 15. A communicationmethod for controlling at least one terminal communicating with anetwork including at least one forwarding device for forwarding apacket, and a control device for controlling said forwarding device inaccordance with a request from said forwarding device, said methodcomprising: receiving a processing rule indicating that a packet forcommunicating with a first destination is changed so as to communicatewith a second destination, from said control device; and in a case ofcommunicating with said network, changing a destination of a packet inaccordance with a processing rule that corresponds to said packet byreferring to said processing rule stored in said storage unit.
 16. Thecommunication method according to claim 15, wherein said receiving theprocessing rule comprises receiving the processing rule determined bysaid control device based on a prescribed condition.
 17. Thecommunication method according to claim 16, wherein said receiving theprocessing rule further comprises receiving the processing ruledetermined by said control device based on a policy corresponding to auser of said at least one terminal.
 18. The communication methodaccording to claim 15, wherein said receiving the processing rulecomprises receiving the processing rule determined by said controldevice based on a policy corresponding to a user of said at least oneterminal.